1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a color splitter, manufacturing the same, and an image sensor including the same.
2. Description of the Related Art
Color display devices or color image sensors use a color filter array to respectively display an image having various colors or sense a color of incident light to generate a signal corresponding to one of three colors in each pixel. Most color display devices and color image sensors being currently used employ a red, green, and blue (RGB) color filter method in which, for example, a green filter is disposed for two of four pixels, and a blue filter and a red filter are respectively disposed for the other two pixels. In addition, besides the RGB color filter method, a cyan, yellow, green, and magenta (CYGM) color filter method in which color filters of cyan, yellow, green magenta having a complementary color relationship therebetween are respectively disposed for four pixels may be employed.
A color filter absorbs light other than corresponded colored light, and thus the light use efficiency of the color filter may be lowered. For example, when an RGB color filter is used, only one-third of incident light is transmitted, and the remaining two-thirds thereof is absorbed and is not used, and thus the light use efficiency of the RGB color filter is merely about 33%. Therefore, for color display devices and color image sensors, most light loss occurs in a color filter.
Recently, a color splitter has been used instead of a color filter to improve the light use efficiency of a color display device or a color image sensor. The color splitter separates colors of incident light by using a diffraction or refraction characteristic of light according to wavelengths and transfers the separated colors to respective corresponding pixels. Therefore, a higher light use efficiency may be achieved when a color splitter is used than when only color filters are used.